1. Field of the Invention
The present invention generally relates to video displays wherein electronic video signals in standard TV format are converted into visible images for viewing by human eyes.
2. Description of Prior Art
The information gathered by state of the art sensors such as video cameras, near infra-red cameras, light intensification devices and far-infrared systems like the Forward Looking Infra-Red detector (FLIR) must be presented to the user by means of visible display. A particularly convenient holder for these displays is the head mounted type, resembling ordinary reading glasses or goggles; that leave the user's head, hands and in some cases his eyes free for other tasks. Conventional displays, whether Cathode Ray Tube (CRT), Flat Panel (including Liquid Crystal Displays, Light Emitting Diodes, etc.) or laser projectors, all produce real images on a screen which must be viewed either directly by the eye (such as the case in viewing a conventional CRT computer monitor) or through some form of magnifying eyepiece lens (such as the case of viewing a miniature video recorder display). This arrangement requires considerable space, which is at a premium in head mounted displays.